Erdahl Township was organized in 1877, and supposedly named after "a district in Norway".

As of the census[1] of 2000, there were 343 people, 132 households, and 107 families residing in the township.

There were 186 housing units at an average density of 5.5 per square mile (2.1/km2).

The racial makeup of the township was 99.13% White, 0.29% Native American, and 0.58% from two or more races.

16.7% of all households were made up of individuals, and 5.3% had someone living alone who was 65 years of age or older.